SEMICON West Preview: What’s Next for MEMS?

SEMICON West Preview:

What’s Next for MEMS?

By Paula Doe, SEMI

While MEMS sensors and
actuators are key to enabling most of the high profile markets of tomorrow,
from wearables to smart objects in the Internet of Things, MEMS companies face
challenges today in transitioning to those new opportunities as basic MEMS
devices increasingly becoming commodities. Large corporations are hiring their
own inhouse MEMS engineers, as standard platforms ease integration and programmable
ASICs ease design spins, and new materials and smarter software enable new
applications.

Tough competition: Much of the growth in the MEMS market in 2013 was concentrated at a
handful of companies, including Bosch, Knowles, Canon, Avago, and InvenSense.
Chinese microphone suppliers AAC and Goertek also saw strong growth, to take
share away from microphone market leader Knowles. But roughly half of the 30 leading companies saw
revenues decline, as increasing unit sales did not make up for falling prices.

Source: Yole Développement

While demand for MEMS devices continues its fast growth
across all sectors, the relentless pressure from consumer markets and
increasing competition continues to drive prices down and reduce margins. “Whatever
the application, from microphones to even advanced 6- and 9-axis inertial sensor
modules, the players who not so long ago dominated a niche with 70-80 percent market share now see their share dropping to
60 percent, 50 percent, or even 40 percent, as more players start to offer
alternative products, and as prices keep coming down even more,” says
Jean-Christophe Eloy, Yole Développement CEO and president, who will speak at
this year’s SEMICON West MEMS program.

MEMS makers have typically reduced cost by reducing die
size, but the sensor die size has stabilized over the last few years as the
sensing elements are reaching their practical limit of scaling. The next generation of inertial sensors will
need to replace the traditional comb drive capacitive technology with some
other technology. Some potential
alternatives range from Qualtre’s BAW-based sensor to Leti/Tronics nanowire
strain gauge that senses piezo-resistance, to mCube’s MEMS on CMOS approach,
but introducing a new technology into a high volume, low price market is a
challenge.

The other path forward for successful companies is scaling to
increasing volumes, and adding increasing value with integration, software or
systems. Others can find it hard to
compete with the high volume and diversified markets of an IDM like Robert
Bosch, which not only sells its sensors but also its systems to the automotive
market, while simultaneously growing a consumer business, notes Eloy.

All that raises the major question of who will invest to add
capacity to support future growth. The
sector has yet to grow enough big fabless companies to support a large volume
foundry business for its idiosyncratic products. InvenSense and Knowles remain the only two
fabless companies to yet make it into the top 30 MEMS makers, and total foundry
production still remains under ~10 percent of total MEMS production value,
according to Yole estimates. That
suggests most future investment will come from the IDMs, who will weigh
additional investment against the return on their IC business, and can
capitalize on synergies with IC and systems business, says Eloy.

New players, more applications

But there’s still a healthy market for smaller volume
products outside the smartphone world, and that’s drawing in more new players.
“What is exciting me is that some of the largest corporations in the world have
now started to get on this MEMS train and hire a team of their own in-house MEMS
guys to look into it,” says Tomas Bauer, Silex Microsystems VP of business
development and marketing, and another speaker at SEMICON West 2014, of the new
kind of foundry customers he’s seeing.
“Instead of just buying a MEMS startup with a prototype, these big
systems makers are now actively developing their own applications. I’d expect we’ll
start to see the results from this shift in the center of gravity in the next
two years or so.”

Development of generic platform modules by multiple
suppliers in the maturing MEMS sector helps ease the entry of these new
players. Silex has focused particularly on integration/packaging platforms with
its through-silicon via technologies, for relatively low-density connections,
but through full-thickness wafers that don’t require special handling or
bonding/debonding. Recently it’s
developed a through-glass version, with~30µm vias at <100µm pitch for
capping RF devices, with more stable permeability than high resistivity
silicon.

The company is also
working with IC foundry partners on a relatively low cost SiP solution using
full-thickness silicon interposers with the these metal vias and four layers of
copper damascene for fine pitch microbumping, allowing the user to buy the interposer
with microbump interface from the foundry, then get final packaging from the OSAT,
without the thin wafer handling and bonding/debonding issues.

Programmable ASIC
platforms speed time to market

As smaller sensors require more sophisticated signal
processing — and as the sensors themselves become more of a commodity — more
value is moving to the ASIC, and spurring development of more support
infrastructure there as well. The ASIC
can account for more than a third of the cost of a complex MEMS device, for
more than a ~$3.5 billion annual business, according to Yole estimates. And now a few suppliers are starting to offer
programmable ASICs to reduce development time and cost.

“It can take a long time to get from a MEMS prototype to an
optimized working device, and a programmable ASIC to use in development can
dramatically reduce time to market, from 18-24 months down to as little as 12
months,” says Scott Smyser, EVP of business development for Egypt-based
ASIC design company Si-Ware. That company is making a version of the
evaluation platform it uses in house available to customers to test their devices.
The development boards offer a programmable ASIC for high performance
single-axis inertial sensors, which can be adjusted for things like different
capacitance ranges, drive frequencies and output parameters, providing the
electronics for modeling and checking the MEMS device to ease the iterations
required to tweak the properties of the sensor and evaluate its match with the
controller. Originally designed for a single axis inertial sensor, the board
can be used for multi-axis devices by daisy chaining units together.
Users so far have ranged from companies looking to enter the
consumer MEMS inertial sensor market to those developing high performance
inertial sensors with particular capabilities. Si-Ware is also working
now to extend the platform for more applications, starting with pressure,
temperature, humidity and other resistant bridge and capacitive sensors.

These speakers will be
joined by Jack Young of Qualcomm Ventures on health and medical sensors, Chris Keimel of GE Global Research on new metal switch technology,
Arjen Janssens of SolMateS on PZT thin film technology, and others, in the MEMS
TechXpot, Tuesday morning, July 8, at SEMICON West, discussing the coming
challenges and opportunities for next generation MEMS. [Register here: www.semiconwest.org/register]

This MEMS event at
SEMICON West 2014 is produced in conjunction with the MEMS Industry Group, which will also host its annual party Wednesday evening.